Automatic lubrication system

ABSTRACT

An automatic lubrication system for conveyors and the like, said system comprising means for initiating a lubrication cycle whereby a lubricant agitator and pump are sequentially actuated to deliver lubricant to a dispensing passageway, a timer and relay arrangement effective to open a lubrication solenoid valve to permit a quantity of lubricant to flow into the dispensing passageway and subsequently open a gas solenoid valve to blow gas through the passageway and expel substantially all of the lubricant therefrom onto the member being lubricated, in such a manner that dripping of the excess lubricant or clogging of the passageway is eliminated.

United States Patent [191 Mclntire et al.

[ AUTOMATIC LUBRICATIION SYSTEM [75] Inventors: Nathan E. Mcllntire;Zelma M.

Porter, both of Clarksville, Tenn.

[73] Assignee: Elk Craft, lnc., Clarksville, Tenn.

[22] Filed: Mar. 21, 1972 21 Appl. No.1 236,756

[52] 11.5. C1. 184/6 R, 184/15 R, 184/56 R [51] Int. Cl. lFl6n 7/30 [58]Field of Search 184/7 R, 7 D, 6.28,

184/56 R, 15 R, 15 B; 165/85; 222/22; 259/95, 96, 43, 44

[56] References Cited UNITED STATES PATENTS 3,116,810 1/1964 Olson184/15 B 3,481,431 12 /1969 Dorsey 184/7 D 2,590,007 3/1952 Griswold....259/44 X 3,595,341 7/1971 Oglesbee 184/6 R 1 Jan. 15, 1974 3,581,8456/1971 Van Nederynen 184/7 D Primary Examiner-Manuel A. AntonakasAttorney-Harvey B. Jacobson [57] ABSTRACT permit a quantity of lubricantto flow into the dispensing passageway and subsequently open a gassolenoid valve to blow gas through the passageway and expelsubstantially all of the lubricant therefrom onto the member beinglubricated, in such a manner that dripping of the excess lubricant orclogging of the passageway is eliminated.

5 Claims, 8 Drawing Figures I ll" PAIENTEUJAN 1 51914 sawzafa 9 M Q iAUTOMATIC LUBRICA'IIION SYSTEM In the past, various conveyor lubricationsystems have been proposed. More recently, the use of solid orsemi-solid lubricants such as Molybdenum Disulfide has become commonsince such provides most desirable qualities for lubricating conveyorparts and the like. While such types of lubricants are highly desirablefor these purposes, they require periodic stirring or agitation in orderto prevent settling or separation of the lubricant particles from thesurrounding liquid medium which facilitate easy movement and flow of thelubricant. In addition, if exposed to the atmosphere for extendedperiods of time, the liquid medium tends to dry up, whereby thelubricant assumes a solid or semisolid consistency which may easily clogsmall lubricant ports and passageways. Thus, conventional conveyorlubrieating systems have proven unsuccessful for the handling ofMolybdenum Disulfide or similar lubricants due to the agitationrequirements and clogging problems. Furthermore, it is apparent thatmost conventional lubricating systems require periodic manual switchingand are not truly automatic in nature.

Therefore, it is an object of the present invention to provide a novelconveyor lubricating system which may be operated without manualswitching or attention and which includes means for effectively handlinglubricants such as Molybdenum Disulfide without clogging passageways orthe like.

Another object of the present invention is to provide a unique conveyorlubricating system which includes means for automatically dispensing alubricant during preselected time intervals and in an efficient manner,whereby the conveyor members to be lubricated are synchronized with thelubricant dispensing device to assure proper lubrication of each member.

It is a further object of the present invention to provide a versatileautomatic lubrication system including a lubricant dispensing tube whichis automatically filled with a predetermined volume of lubricant whichis subsequently expelled from the tube by ablast of gas, such thatinsufficient residue remainsinthe tube to permit dripping or clogging.

Still another object of the present invention is to provide a novelautomatic lubrication system capable of dispensing both conventionalpetroleum lubricants, as well as Molybdenum Disulfide types, which isfully automatic, and which includes many standard commercially availablecomponents of proven reliability, whereby the overall system is durable,long lasting and relatively inexpensive to manufacture and maintain.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout.

FIG. I is a simplified block diagram of the automatic lubrication systemof the present invention.

FIG. 2 is a side elevation of the lubricant system of the presentinvention mounted to a typical conveyor construction.

FIG. 3 is a front elevational view of the control panel associated withthe present invention.

FIG. 4 is an enlarged elevational view of the sensors and solenoidsassociated with the present invention.

FIG. 5 is a sectional view taken along section -5 of FIG. 4. Y

FIG. 6 is an elevational view ofthe agitator associated with the presentinvention, with sections removed.

FIG. 7 is an enlarged sectional view of the float switch mechanismassociated with the agitator shown in FIG. 6.

FIG. 8 is a sectional view of one of the lubricant dispensing nozzlesassociated with the present invention.

Referring now, more particularly, to FIG. 1 of the drawings, asimplified block diagram of the automatic lubrication system of thepresent invention is generally indicated by the numeral 10 and includesa cycle sensor 12 which is tripped'by an actuator attached to theconveyor as it passes a predetermined point along its path of travel.The cycle sensor is effective to energize an agitator 14 by way of anagitator pump selector relay 16, power being furnished through aconventional motor relay 18. The agitator is operated for a preselectedtime interval sufficient in length to agitate or stir the lubricant toassure proper mixing with its fluid medium. Subsequent to agitation, alubricant pump 20 is energized and the lubricant dispensing system isconditioned to receive lubricant upon energization of a lubricantsolenoid valve 22 through a timer 24 and relay 26. This operation isinitiated by way of a trip sensor 28 which is actuated by each movingmember to be lubricated as it advances past a predetermined point.Subsequent to operation of the lubricant solenoid valve, an air solenoidvalve 30 is actuated to provide a gas blast which expels the lubricantfrom a lubrication tube onto the moving member to be lubricated. The gasblast operation is effected by way of a timer 32 and relay 34, which areactuated upon completion of the time interval of lubrication timer 24.

Referring briefly to FIG. 2, the structure of the lubrication'system ofthe present invention is illustrated to include a control panel 36provided with an incoming source of voltage, not illustrated, and anincoming gas line 38 connected to a conventional source of pressure, notshown. The control panel houses the timers, relays, and other electricalcontrols which perform the automatic functions of the lubricationsystem, as hereinafter explained. A typical overhead conveyor 40, of aconventional type is provided with an elongated chain 42 carried by aplurality of spaced roller bearings 44 which ride along an l-beam orrail $6 to advance loads or handle materials in a manner well known.

Since each roller bearing may be subjected to heavy load and longperiods of operation, it is most often necessary to provide periodiclubrication to the moving parts of each roller bearing. This is achievedby way of a pair of lubricant dispensing tubes 48 which are mounted withtheir open ends positioned for periodic alignment with the rollerbearings as they are advanced during use of the conveyor.

A source of lubricant, such as Molybdenum Disultide, is provided in acontainer or reservoir 50 and delivered to dispensing tubes 48 by way ofa conventional pump 52, subsequent to sufficient stirring or mixing byway of an agitator 54. After the lubricant has been properly agitated,the lubricant pump circulates the lubricant through a delivery line 56,past a T-connection 58 to a return line MI. The lubricant is normallyprevented from flowing to the dispensing tube 48 by way of a lubricantsolenoid valve 62 which is normally closed.

Electrical signals are provided from control panel 36 to effect openingof solenoid valve 62 for a time interval sufficient to at leastpartially fill the dispensing tube with lubricant. It should be notedthat the time interval during which solenoid valve 62 is open isrelatively short in duration, such that the passage of lubricant throughthe exhaust ends of the dispensing tubes is prevented. After thedelivery tubes have been filled with lubricant, a second signal isprovided from control panel 36 which is effective to open a gas solenoidvalve 64, thereby permitting the flow of air, or other gas from inletline 38 through line 66 and line 68 to the dispensing tubes in order toforce or expel substantially all of the lubricant previously pumped intothe dispensing tubes. This gas blast operation is synchronized with theposition of each conveyor roller to assure that the lubricant isexpelled at the proper location on each roller member.

The lubrication system is further provided with a pair of sensors 70 and72, corresponding to blocks 12 and 28 respectively in FIG. 1, whichfurnish signals to the control panel which are indicative of thepositions of the moving members to be lubricated. At least one of themoving members associated with the continuous conveyor is provided witha tab or trip element 74 which extends in a direction which is effectiveto actuate cycle sensor 70. Preferably, the continuous conveyor isprovided with a single trip element, such that the cycle sensor isacutated upon each complete revolution of the conveyor. Of course, ifdesired, more than one trip element may be utilized when found to beadvantageous to the lubrication system operation.

Trip sensor 72 is positioned in such a manner that it is not actuated bythe passage of trip element 74, but is actuated by the passage of eachroller bearing. The trip sensor provides signals to the control panelwhich initiate preselected time intervals to assure propersynchronization for dispensing of the lubricant. Preferably, sensors 70and 72 are comprised of conventional limit switch construction which aremechanically actuated by the trip element 74 and roller bearings 44,respectively. However, the use of other sensing devices, such asproximity limit switches, or electric eye systems, may be utilized withthe system of the present invention, if desired.

Referring again to FIG. 1 ofthe drawings, the operation of the circuitryassociated with the present invention will be more fully explained. Thesystem is fed by an incoming source of voltage 76, preferably 120 VAC,which is fed to motor relay 18 by way ofa fuse 78. Voltage is also fedto a master timer 80,.such as a skip-a-day time clock of a conventionaltype which may be adjusted to enable and disenable the lubricationsystem in accordance with the anticipated work schedule and use of theassociated conveyor beinglubricated. With the master timer in the ONcondition, voltage is furnished to a low voltage supply 82 by way of afuse 84. A reduced control voltage is normally fed to a relay 86provided with a pair of normally open contacts connected to motor relayl8.

The lubrication cycle is initiated by a signal from cycle sensor 12 to asequence selector switch 88 by way of a step relay 90. The step relayand sequence selector switch are conventional types which may bearranged to provide an output signal upon completion of a preselectednumber of input pulses from a signal source, such as the cycle sensor12. Thus, the system may be set up to dispense lubricants every othertime the cycle sensor is actuated or every third time and so on,depending upon the lubricant requirements.

Assuming that the cycle sensor has been actuated to initiate alubrication cycle, the output signal from sequence selector switch 88 iseffective to energize relay 86 which, in turn, effects closure of motorrelay 18 to provide primary voltage to the agitator pump selector relay16. At the same time, an off relay 92 is actuated to initiate operationof an agitator timer 94 for a preselected ON time delay. Thus, agitator14 is energized and continues to operate until agitator timer 94completes its time interval, upon which a ready relay 96 is actuatedwhich, in turn, conditions selector relay 16 to deenergize agitator 14and energize pump 20.

Actuation of the ready relay 96 is also effective to condition thelubrication dispensing portion of the system to receive lubricant fromthe reservoir illustrated in FIG. 2 and to dispense such in accordancewith the above description. When trip sensor 28 is actuated by a movingmember of the conveyor, the input signal from ready relay 96 passesthrough a latch relay 98 to a synchronizing delay timer 100. This timeris a conventional type interval timer with relatively fine adjustment toassure proper synchronization between the positions of the movingmembers and the lubrication operation.

Upon completion of the synchronization time delay interval, a signal isfed to lubrication timer 24 which, in turn, actuates lubrication relay26 to open the lubrication solenoid valve 22. The lubrication solenoidvalve remains open for a time interval which is preselected to at leastpartially till the lubricant dispensing tube, as explained above. Uponcompletion of the time interval of lubrication timer 24, a signal is fedto air timer 32 which, in turn, actuates relay 34 to effect opening ofthe air solenoid valve 30. At this point in the systems operation, ablast of air or other gas passes through the lubricant dispensing tubesto expel substantially all of the lubricant previously depositedtherein.

Upon completion of the gas blast operation, an output signal from airtimer 32 is fed to a latch release mechanism 102 which is effective torelease relay 98, unless the trip sensor 28 is being actuated at thesame time, in which case the system would continue to function. Assumingthat trip sensor 28 is not being actuated at the same instant as thelatch release signal is fed to relay 98, the latch relay is deactuated,thereby conditioning the lube dispensing portion of the system for arepeat operation.

After each of the moving members has been lubricated in accordance withthe above description, subsequent actuation of the cycle sensor 12 iseffective to actuate the step relay and sequence selector switch 88 todeactuate relay 86. Opening of relay 86 provides a signal to an offdelay timer 104 which delays deactuation of the off relay 92, such thatthe system continues to function for a preselected time delay intervalto assure that the remaining unlubricated moving members are lubricatedbefore the system is shut down. Normally this off delay is requiredsince several of the moving members adjacent to trip element 74 were notoriginally lubricated due to the fact that the agitator was stirring thelubricant prior to the pumping of such to the lubricant dispensingportion of the system.

tions of the electrical system associated with the present invention. Inaddition, a plurality of time interval adjustment knobs 110 associatedwith the abovementioned timers are provided for the convenientadjustment of each time interval. A sequence selector switch knob 112 isprovided to select the desired mode of operation, whereby the number ofcycle sensor operations to recycle the system may be preset. The mastertimer 80 is mounted at the right hand side of the control panel adjacentto an agitator timer adjustment knob 114 and a gas pressure indicator116 associated with the gas blast portion of the system. In addition,the control panel is provided with readily replaceable fuses at 118 andassociated indicating lights 120.

With reference to FIGS. 4 and of the drawings, the structuralarrangement of the solenoids and sensors may be seen in more detail. Itwill be appreciated that cycle sensor 70 is transversely offset fromtrip sensor 72, such that operation of one, is independent of the other.Cycle sensor 70 is providedwith an actuation member 122 which extendsdownwardly into the path of travel of the trip element 74, such that theactuator is reciprocated in an upward direction as a roller 124associated therewith makes contact with the trip element. This operationprovides the above described pulse to the step relay.

Similarly, trip sensor '72 is provided with an actuator 126 and roller128 which are transversely spaced from those of the cycle sensor and arepositioned within the path of travel of the roller bearings 44. As theconveyor is advanced, the roller bearings reciprocate actuator 126 in avertical direction, thereby effecting operation of the trip sensor toprovide a signal to latch relay 98 which, in turn, is effective toinitiate a lubrication dispensing operation.

Solenoid valves 62 and 64 are, preferably, mounted on top of theconveyor I-bearn 46 in close proximity to the fluid dispensing tubes.The opened ends of the dispensing tubes are provided with nozzle members1311 which are of such a configuration to provide the desired spraypattern. FIG. 8 illustrates a typical nozzle member which is shaped toprovide a relatively narrow spray which may be concentrated upon themoving members to be lubricated. It should be noted, however, thatnozzle members other than that illustrated or additional solenoid valvesmay be utilized, if desired.

FIGS. 6 and 7 illustrate the structural arrangement of the agitatorassembly associated with the present invention. The reservoir orcontainer 50 of desired capacity, is provided with a paddle member 132which is rotated by an agitation motor 134 through a drive train 136 andoutput shaft 138. In addition, after proper agitation of the lubricanthas been completed,'pump 52 draws the lubricant through an outlet tube140 for delivery of the lubricant to the dispensing portion of thesystem, as explained above. The lubricant may be returned to thereservoir by way of a return inlet 142 preferably located above thenormal level of the lubricant.

The agitator assembly is also provided with a float responsive switch144 connected to a buoyant member 146, such that the switch is actuatedwhen the lubricant reaches a predetermined low level, whereby anindicating light is energized on the control panel. In addition, thelubricant level sensor is connected to the low voltage supply 82, asshown in FIG. 1, and is effective to disconnect supply 82 from sequenceselector switch 88 when the low lubricant level is reached toautomatically shut down the system.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed is:

1. In combination: an automatic lubrication system and a conveyor havingmoving members requiring lubrication, said system comprising: alubricant dispensing tube with a lubricant receiving end and an openedend adapted to permit the exhaust of lubricant therethrough to a movingmember to be lubricated, electrical means including means for sensingthe passage of the moving members past a predetermined point along theconveyors path of travel, a source of lubricant under pressure,lubricant valve means opened in response to signals from said sensingmeans for communieating said source of lubricant with the lubricantreceiving end of said dispensing tube for a preselected time interval toat least partially fill said dispensing tube with lubricant, a source ofgas pressure, and gas valve means opened in response to signals fromsaid electrical means subsequent to filling of said dispensing tube withlubricant for communicating said gas pressure source with saiddispensing tube at a point remote from said open end to blow thelubricant therefrom through said opened end, said electrical meansincluding lubricanttimer means responsive to said sensing means to opensaid lubricant means for a preselected time interval corresponding to apredetermined volume of lubricant permitted to flow into said dispensingtube, gas timer means for initiating a gas time interval in response tothe completion of said lubricant time interval to open said gas valvemeans to blow the lubricant from said dispensing tube, relay meansresponsive to the completion of said gas time interval to condition saidlubricating system to reset said timer means for repeat of thelubricating and gas blast operations, and delay timer means responsiveto said sensing means upon actuation thereof by the passage of a movingmember to be lubricated to initiate a preselected time delay intervaland subsequently effect actuation of said lubricant timer means toinitiate said lubricant time interval, said time delay interval beingeffective to synchronize the position of each moving member with saidgas time interval such that the moving member being lubricated isproperly positioned relative to-the opened end of said dispensing tube.

2. A lubricant system for handling a solid lubricant in a fluid medium,said lubricant system comprising: an open ended lubricant dispensingmember, a reservoir of solid lubricant in a fluid medium, passagewaymeans defining a delivery path from said reservoir and a return path tosaid reservoir, said return path being in direct communication with saiddelivery path, pump means associated with said passageway means forcontinuously circulating said lubricant and associated fluid mediumthrough said passageway means, and selectively operable valve meansconnected to said passageway means at the junction of said delivery pathand said return path and operable in an open position to permit aquantity of said lubricant and fluid medium to flow from said deliverypath to said dispensing member, continuous circulation of said lubricantand fluid medium by said pump means preventing clogging of saidpassageway means while said valve means is closed.

3. The system set forth in claim 2 including gas blast means connectedto said dispensing member at a point remote from the open end thereof toselectively blow the lubricant and associated fluid medium therefrom. 4.In combination with equipment lubricated with a lubricant having afluency property that deteriorates under static conditions, alubricating system comprising a reservoir containing said lubricant,conduit means connected to the reservoir for conducting the lubricant ina closed circuit, circulating pump means connected to the conduit meansfor inducing flow of the lubricant through said circuit to maintainthelubricant in a state of motion and thereby sustain said fluencyproperty, dispensing means for discharging said lubricant into saidequipment, and valve means connecting the conduit means to thedispensing means for intermittently supplying the lubricant to thedispensing means only while in said state of motion.

5. The combination of claim 4 including control means for programmingoperation of the pump means and the valve means to open the valve meansonly while the lubricant is under a dynamic pressure head induced by thepump means prior to opening of the valve means.

1. In combination: an automatic lubrication system and a conveyor having moving members requiring lubrication, said system comprising: a lubricant dispensing tube with a lubricant receiving end and an opened end adapted to permit the exhaust of lubricant therethrough to a moving member to be lubricated, electrical means including meaNs for sensing the passage of the moving members past a predetermined point along the conveyor''s path of travel, a source of lubricant under pressure, lubricant valve means opened in response to signals from said sensing means for communicating said source of lubricant with the lubricant receiving end of said dispensing tube for a preselected time interval to at least partially fill said dispensing tube with lubricant, a source of gas pressure, and gas valve means opened in response to signals from said electrical means subsequent to filling of said dispensing tube with lubricant for communicating said gas pressure source with said dispensing tube at a point remote from said open end to blow the lubricant therefrom through said opened end, said electrical means including lubricant timer means responsive to said sensing means to open said lubricant means for a preselected time interval corresponding to a predetermined volume of lubricant permitted to flow into said dispensing tube, gas timer means for initiating a gas time interval in response to the completion of said lubricant time interval to open said gas valve means to blow the lubricant from said dispensing tube, relay means responsive to the completion of said gas time interval to condition said lubricating system to reset said timer means for repeat of the lubricating and gas blast operations, and delay timer means responsive to said sensing means upon actuation thereof by the passage of a moving member to be lubricated to initiate a preselected time delay interval and subsequently effect actuation of said lubricant timer means to initiate said lubricant time interval, said time delay interval being effective to synchronize the position of each moving member with said gas time interval such that the moving member being lubricated is properly positioned relative to the opened end of said dispensing tube.
 2. A lubricant system for handling a solid lubricant in a fluid medium, said lubricant system comprising: an open ended lubricant dispensing member, a reservoir of solid lubricant in a fluid medium, passageway means defining a delivery path from said reservoir and a return path to said reservoir, said return path being in direct communication with said delivery path, pump means associated with said passageway means for continuously circulating said lubricant and associated fluid medium through said passageway means, and selectively operable valve means connected to said passageway means at the junction of said delivery path and said return path and operable in an open position to permit a quantity of said lubricant and fluid medium to flow from said delivery path to said dispensing member, continuous circulation of said lubricant and fluid medium by said pump means preventing clogging of said passageway means while said valve means is closed.
 3. The system set forth in claim 2 including gas blast means connected to said dispensing member at a point remote from the open end thereof to selectively blow the lubricant and associated fluid medium therefrom.
 4. In combination with equipment lubricated with a lubricant having a fluency property that deteriorates under static conditions, a lubricating system comprising a reservoir containing said lubricant, conduit means connected to the reservoir for conducting the lubricant in a closed circuit, circulating pump means connected to the conduit means for inducing flow of the lubricant through said circuit to maintain the lubricant in a state of motion and thereby sustain said fluency property, dispensing means for discharging said lubricant into said equipment, and valve means connecting the conduit means to the dispensing means for intermittently supplying the lubricant to the dispensing means only while in said state of motion.
 5. The combination of claim 4 including control means for programming operation of the pump means and the valve means to open the valve means only while the lubricant is under a dynamic pressure head induced by the pump means prior to opening of the vaLve means. 